Leviticus 16

"Then Aaron shall cast lots for the two goats: one lot for the Lord and the other lot for the scapegoat.  And Aaron shall bring the goat on which the Lord’s lot fell, and offer it as a sin offering.  But the goat on which the lot fell to be the scapegoat shall be presented alive before the Lord, to make atonement upon it, and to let it go as the scapegoat into the wilderness." vv.8-10

Read chapter 16.
The day of atonement was to be done one a year (v.34).  Two goats were to be brought to the altar one to be killed and the other to be set free.  By the Urim an the Thummim that was in the holy garments of the priest that performed these duties they would cast the lot to see which goat was to the Lord as a sin offering and which goat would be set free.  It's cool to see how both these goats are a type of Christ.  Christ like the goat slaughtered for the sin offering was an example of Christ crucifixion on the cross dying for our sin.  The scapegoat is also a type of Christ in that Aaron would lay his hands on the goat and pronounce all the iniquities of the children of Israel so that the goat would bear them and be set free into the wilderness taking the sins away out of the land of Israel.  So too Christ resurrected is alive, who bore all our sins.  Where there's atonement, or reconciliation, there must be forgiveness.  We too are like the live scapegoat being set free to life everlasting.